Stories with Tag email server

• How IMAP works under the hood

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  Posted: 2025-03-29 09:05:33

  Verbose tl;dr

  IMAP (Internet Message Access Protocol) allows multiple clients to access and manage email stored on a server. Instead of downloading messages like POP3, IMAP synchronizes the client's view with the server's mailbox state. Clients issue commands to interact with messages on the server – reading, deleting, moving, etc. – and the server responds with status updates and data. This enables access to the same mailbox from various devices while maintaining consistency. IMAP uses a folder structure on the server, mirroring this on the client, and supports flags for marking messages as read, answered, deleted, etc., all managed server-side. Connections are typically kept open for continuous synchronization and responsiveness.

  This blog post provides a detailed introduction to the inner workings of the Internet Message Access Protocol (IMAP), explaining how it allows email clients to access and manage email messages stored on a remote mail server. Unlike POP3, which downloads messages to a local client and typically removes them from the server, IMAP maintains all messages on the server, enabling access from multiple devices and clients simultaneously.

  The post begins by outlining the client-server architecture of IMAP, emphasizing that messages reside on the server while clients interact with them remotely. It then delves into the concept of folders (also known as mailboxes), which are used to organize emails on the server. IMAP clients can create, rename, and delete these folders, providing a structured way to manage emails. The post clarifies that these server-side folders don't necessarily map directly to local folders on a client, allowing for flexibility in how users organize their mail across different devices.

  A key aspect of IMAP is its stateful nature. The post explains that a connection between the client and server is established, and throughout this connection, the client keeps track of the state of the server's mailbox. This includes things like which messages have been read, flagged, or replied to. This synchronization of state is crucial for providing a consistent experience across different clients accessing the same mailbox. Commands issued by the client modify this server-side state, reflecting changes across all connected clients.

  The post then proceeds to describe the fundamental commands used in IMAP communication. These commands, formatted as plain text, enable clients to perform actions like selecting a folder, fetching message headers, retrieving the full message body, searching for specific emails, and managing flags (such as seen, answered, or deleted). The server responds to these commands, providing the requested data or confirming the successful execution of an action. The post provides illustrative examples of these command-response interactions to clarify the communication flow.

  Furthermore, the post highlights the role of UID (Unique Identifier), a persistent identifier assigned to each message within a mailbox. This UID remains constant even if the message is moved to a different folder, unlike message sequence numbers which are relative to the current folder and can change. This stability allows clients to reliably track messages across sessions and different folder organizations.

  The post concludes by briefly mentioning IDLE, an extension to the IMAP protocol that allows clients to receive real-time notifications of new messages arriving in the mailbox. This push notification functionality enhances the responsiveness of email clients without requiring constant polling of the server. Overall, the post provides a comprehensive yet accessible overview of the core concepts and mechanisms underlying IMAP, offering a solid foundation for understanding how email clients interact with remote mail servers.

  • imap
  • Email
  • Protocol
  • Technical
  • Under the Hood
  • How It Works
  • networking
  • Client-Server
  • Internet Protocol
  • Email Client
  • email server

  Summary of Comments ( 33 )
  https://news.ycombinator.com/item?id=43513967

  Verbose tl;dr

  Hacker News users discussed various aspects of IMAP, focusing on its complexity and alternatives. Some praised the article for clearly explaining a convoluted protocol, while others shared personal experiences and frustrations with IMAP's quirks, such as inconsistent behavior across servers. A few commenters suggested exploring simpler email protocols like POP3 for basic use cases or diving deeper into specific IMAP features. The discussion also touched on email clients, synchronization challenges, and the benefits of storing emails locally. Several users recommended Dovecot as a robust IMAP server implementation.

  The Hacker News post titled "How IMAP works under the hood" (linking to https://blog.lohr.dev/imap-introduction) sparked a modest discussion with a few noteworthy comments.

  One user highlighted the importance of understanding IMAP for troubleshooting email issues, mentioning how it helped them diagnose a problem with their email client constantly re-downloading emails. They emphasized the value of knowing the underlying mechanics of the protocol.

  Another commenter discussed the complexities of syncing email across multiple devices, acknowledging IMAP's strengths in this area while also pointing out potential drawbacks, like storage limitations and performance issues with large mailboxes. They mentioned how these limitations often lead users to consider alternative solutions like local caching or different synchronization methods.

  A further comment praised the original article for its clear and concise explanation of IMAP, expressing appreciation for the author's approach to breaking down a complex topic into easily digestible parts. They specifically called out the helpfulness of the diagrams included in the blog post.

  Finally, one commenter briefly touched on the historical context of IMAP, contrasting it with older protocols like POP3 and highlighting the evolution of email retrieval methods. They briefly alluded to the implications of each approach for data storage and accessibility.

  While the discussion wasn't extensive, these comments provide valuable perspectives on the practical implications of IMAP, its benefits and drawbacks, and its place within the larger history of email technology. They don't delve deeply into highly technical details, but offer helpful context and personal experiences related to using and understanding the protocol.

• Mox – modern, secure, all-in-one email server

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  Posted: 2025-03-05 01:58:11

  Verbose tl;dr

  Mox is a self-hosted, all-in-one email server designed for modern usage with a focus on security and simplicity. It combines a mail transfer agent (MTA), mail delivery agent (MDA), webmail client, and anti-spam/antivirus protection into a single package, simplifying setup and maintenance. Utilizing modern technologies like DKIM, DMARC, SPF, and ARC, Mox prioritizes email security. It also offers user-friendly features like a built-in address book, calendar, and support for multiple domains and users. The software is available for various platforms and aims to provide a comprehensive and secure email solution without the complexity of managing separate components.

  The website introduces Mox, a self-hosted email server solution designed for contemporary needs, emphasizing security and ease of use. It aims to provide an all-in-one package, simplifying the often complex process of setting up and maintaining an email server. Mox incorporates modern email technologies, including IMAP, POP3, and SMTP, ensuring compatibility with existing email clients. It prioritizes security with features like two-factor authentication, DMARC, DKIM, and SPF, mitigating common email security threats such as spam and phishing attempts. The software is designed with a focus on user-friendliness, offering a web-based administration interface that streamlines server management tasks like user creation, quota management, and configuration adjustments.

  Mox is built using Rust, a programming language known for its memory safety and performance characteristics, which contribute to the server's stability and efficiency. The website highlights the single binary deployment method, simplifying installation and updates by reducing dependencies and potential conflicts. Furthermore, Mox supports SQLite as its database backend, eliminating the need for external database servers and simplifying setup. The website also underscores Mox's low resource usage, making it suitable for deployment on smaller devices or virtual private servers. Although presented as a fully-featured solution, the website mentions the software is still in its early stages (beta), indicating ongoing development and potential future enhancements. It encourages community involvement and contributions through its open-source nature, hosted on GitHub. The website provides clear instructions for installation and configuration, along with links to the GitHub repository and documentation, offering users resources for support and further exploration of the software.

  • email server
  • self-hosted email
  • email hosting
  • mox
  • xmox
  • privacy
  • Security
  • all-in-one
  • modern
  • imap
  • SMTP
  • POP3
  • Anti-spam
  • Anti-virus
  • Webmail
  • Open Source
  • Rust

  Summary of Comments ( 255 )
  https://news.ycombinator.com/item?id=43261729

  Verbose tl;dr

  Hacker News users discuss Mox, a new all-in-one email server. Several commenters express interest in the project, praising its modern design and focus on security. Some question the practicality of running a personal email server given the complexity and maintenance involved, contrasted with the convenience of established providers. Others inquire about specific features like DKIM signing and spam filtering, while a few raise concerns about potential vulnerabilities and the challenge of achieving reliable deliverability. The overall sentiment leans towards cautious optimism, with many eager to see how Mox develops. A significant number of commenters express a desire for simpler, more privacy-respecting email solutions.

  The Hacker News post "Mox – modern, secure, all-in-one email server" generated a moderate number of comments discussing various aspects of the Mox email server and self-hosting email in general.

  Several commenters expressed interest in Mox, praising its modern approach and integrated feature set. They appreciated the focus on security and the potential for a streamlined, user-friendly experience compared to setting up and maintaining individual email server components. The all-in-one nature of Mox, incorporating anti-spam, anti-virus, and full-text search, was seen as a major advantage.

  Some users raised concerns and questions about specific features and functionalities. Discussion arose around the database backend used by Mox, with some expressing preference for PostgreSQL due to its robustness and maturity. Questions were also raised about the webmail client, calendar integration, and the overall performance and scalability of the system, especially for handling larger mailboxes.

  The topic of DKIM (DomainKeys Identified Mail) signing and its implementation in Mox was brought up, highlighting the importance of this security measure for email authentication. Relatedly, the challenges of email deliverability and avoiding spam filters were discussed, acknowledging the complexities involved in self-hosting email.

  Several commenters shared their experiences with self-hosting email, some highlighting the difficulties and maintenance overhead involved. They discussed alternative solutions like Mail-in-a-Box and Mailcow, comparing their features and ease of use to Mox. The relative simplicity and integrated nature of Mox was seen as a potential advantage over these alternatives.

  A few commenters expressed skepticism about the viability of self-hosting email for average users, citing the technical expertise required and the ongoing maintenance burden. They suggested that managed email solutions might be a more practical option for most people.

  Overall, the comments reflect a mix of enthusiasm for Mox's potential as a modern and secure email server solution and pragmatic concerns about the complexities of self-hosting email. The discussion provided valuable insights into the challenges and considerations involved in choosing an email solution, highlighting the trade-offs between control, security, and ease of use.